Battery-electrode



L. MAISEL.

BATTERY ELECTRODE. APPLICATION FILED DEC-2], l9l8.

1,375,306, PatenM A1111 1921.

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BATTERY ELECTRODE.

APPLICATION FILED D EC.2I,' 19l8.

Patented Apr. 19, 1921.

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a, 4- .mi $7M L. MAISEL.

BATTERY ELECTRODE.

APPLICATION FILED DEC.2I, I918.

Patented Apr. '19, 1921.

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LORENZ MAISEL, 0F MADISON, WISCONSIN, ASSIGNOIR- TO BURGESS BATTERY COMPANY. OF MADISON, WISCONSIN, A CORPORATION OF WISCONSIN.

BATTERY-ELECTRODE.

Specification of Letters Patent. Patented Apr. 1 9 1921 Original application filed October 11, 1918, Serial No. 257,691.

Divided and this application filed-December 21, 1918. Serial No. 267,752.

To all whom it may concern:

Be it known that I, LORENZ MAISEL, residing at Madison, in the county of Dane, State of Wisconsin, have invented certain new and useful Improvements in Battery- Electrodes; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

The present invent-ion relates to battery electrodes, and more particularly to electrodes of the cup or container type, and is a division of my prior application, Serial No. 257,691, filed October 11, 1918.

It is desired to produce an electrode in the form of a seamless, fluid-tight cup or container of wrought zinc, since electrodes of that character completely dispense with the usual soldered joints which are objectionable both because of the expense of soldering, and because of the local action which is apt to take place at the points where the solder comes into contact with the corrosive electrolyte of the battery.

According to the invention, as preferably practised, a sheet or ribbon of zincis fed across the surface of an annular die, between the latter and the movable punch arrangedthereabove. The punch, on descending, cooperates with the die in stamping or cutting out a circular blank of zinc, which is clamped betwe n the punch and a pressure ring located within the die. As the punch continues to descend, the pressure ring yields, and it elf moves downward at the same rate ofs eed as the punch, thus maintaining a uniform degree of pressure upon the blank which remains gripped between the ring and punch and is drawn out and ironed into cupped or dished form by the action of a preliminary-shaping plunger. The latter is disposed within the aforesaid ring and is caused to gradually enter the punch consequent upon the sinking of the ring, the shaping operation terminating when the ring reaches the limit of its clownward movement. The parts then commence their ascent, and at the conclusion thereof, the blank, which is at that time in the form of a relatively-wide, shallow. cup, is removed from the die and thereafter subjected to a re-shaping action, which is repeated until the cup has finally been ironed out and elongated into a cylinder or tube of the required length and diameter. This action is effected by means of pairs of cooperating dies and plungers, the diameters of the working portions of the dies and, hence, the diameters of the plungers, decreasing with each succeeding pair. provided with an interior, circumferential ledge or shoulder forming a constricted throat through which the work is forced by the plunger, the lower edge of the shoulder serving as a stripper to remove the work from the plunger as the latter ascends. The ironing action, however, affects only the sides and the outer portion of the bottom of the cup which are thereby slightly thinned, whereas the central portion of the bottom of the cup has the same thickness as the original blank and is left unchanged as to size throughout the several re-shaping actions. In the accompanying drawing which shows the preferred form of apparatus for making the improved seamless zinc cup:

Figure 1 is a longitudinal section of the The dies are each apparatus, taken on line 1-1, Fig. 2, the

Fig. 3 is a View similar to Fig. 1, but

showing one of the re-drawing plungers and its associated die;

Figs. 4, 5 and 6 are detail sectional views, showing successive steps in the preliminary shaping or cupping of the blank;

Fig. 7 shows both a face view and an edge view of the blank;

Fig. 8 shows, in vertical section, the shapes which the blank assumes during its successive treatments;

F ig: 9 is a vertical sectional view of the finished cup or container; Fig. 10 is a vertical sectional view showng a nest of cups arranged so as to disclose the relative changes in size and shape which take place as a result of the successive operations; and

Fig. 11 is a vertical sectional view showing the cup or container in use.

Referring more particularly to the drawing, there is shown in Figs. 1 and 2 the form of press which at present seems most suitable for carrying out the preliminary cutting and shaping operations. and which comprises co-acting upper and lower members designated generally 1 and 2; one of said members, in this case, the upper memher, being movable' with relation to the other, as will be understood. The mechanism for effecting such movement may be of any desired character, and since it forms no part of the actual invention, it has not been illustrated.

The aforesaid upper or moving member or element 1 of the press preferably consists of a hollow, cylindrical punch 3, which is fastened to a cross-head 4 and is provide-d with an elongated, hollow stem 5 that projects upwardly through an opening in said cross-head, the latter having a pair of dependingpresser pins 6 fastened to its opposite ends. The punch 3 has disposed within it an ejector 7, thestem 8 of which extends upwardly through and beyond the bore of the punch stem 5 and carries a stop 9 .in the form of a collar arranged in said bore to limit the downward movement of the ejector, as hereinafter explained.

The stationary lower element or member 2 comprises a base or bolster 10, upon which is mounted the annulardie 11, the construction and arrangement of parts being such that the punch 3, during its working stroke,

is caused to enter the die, the co-acting edges of the punch and die serving to cut out a circular blank 12 (Fig. 7) of the proper size from the strip or ribbon 13, of zinc, which is suitably fed between the two press elements. The die 11 incloses a pressure ring 14 which is supported in the upper part of said die by means of a plurality of ins or studs 15, the lower portions'of which ex tend through openings in the base 10 and rest at their ends on a second cross-head 16. The latter is slidably mounted on a depending, vertical rod 17, and is yieldingly supported upon the upper end of a buffer sleeve 18, made of rubber or other suitable 'ma terial of like character, the lower end of/the buffer restingupon a cap or collar 19, which is likewise carried by the rod 17 and is itself supported by a nut 20, or its equivalent. The pressure ring 14 is disposed beneath and in co-axial relation with the punch 3, the

two parts having the same, or substantially the same, thickness and diameter and having their confronting edge faces slightly beveled;

The blank 12, when out from the zinc I strip or ribbon 13, initially rests upon the edge face of the ring, and is clamped between said face and the corresponding face of the punch, being held thereby in position to beoperated upon by the preliminary shaping plunger 21: This plunger may, as

The plunger has a height such that the center of its rounded top face is normally flush with the inneredge of the pressure ring, so that it is prevented from acting on the blank until the said pressure ring has been depressed, as will beunderstood from Fig. 1. To effect this, the cross-head 16 is provided with a plurality of upright pins 23, one for each presser pin 6, which project loosely through openings in the base 10 and are disposed exactly in line with the said pins 6, the relative lengths of the pins '23 and 6 being such that they contact with each other just after the out blank has been clam )ed between the pressure ring' and punch As the descent of the movableelement or member 1 continues, the pressure imposed by the pins 6 upon the tops of the pins 23 will force the cross-head 16 downward, the buffer sleeve 18 buckling at that time. The downward movement of said cross-head 16 permitsthe ring 14 to move down with it at the same rate of speed as the descending punch 3 dueto the engagement of the pins 23 by the presser pins 6 with the result that the pressure exerted upon the blank is maintained constant and uniform.' The plunger 21 becomes exposed and during the descent of the ring is, accordingly, enabled to exert its stretching, 5

drawing or ironing action upon the blank,

the latter being gradually given a cupped or dished shape; see Figs. 4, 5 and. 6.

At the conclusion of the downward movement just described, the movable upper member or device 1 commences its ascent, the shapedblank remaining within the punch, while at the same time the ring 14 and its cross-head 16 are pushed upward, owing to the straightening outer expansion of the buffer 18, which thus acts/in a sense as a spring. During this movement, the pres: sifre ring gradually rovers the plunger 21 again, and the latter is gradually withdrawn,

from the punch. The ejector 7 fitted within 0 said punch likewise rises therewith, until the upper end of its stem 8 strikes against a suitable stop (not shown) whereupon the ejector is held stationary during the further movement of the punch, which continues until the stop collar 9 abuts against the bottom wall of the bore of the punch stem 5. When that point is reached, the ejector will occupy a position at or slightly below the lower edge of the punch,, forcing out the blank therefrom, the said blank having at that time the cup-like shape represented by the member a at the left-hand end of Fig. 8.

After having been subjected to the preliminary shaping action, the dished blank or cup 0 undergoes a series of drawing, stretching or ironing actions, each effected by means of a die and cooperating plunger,

of which those shown in F i 3 are typical. The working portions of ea cdifdie and plunout more and more and proportionately thinned, while at the same time the diameter of the cup is reduced, so that by the time the last re-drawing action has been completed, the cup will have been transformed into a relatively long and narrow tube which is closed at its bottom, as depicted by the member a at the right-hand. end of Fig. 8, the intermediate stages of such transformation bein indicated by the members a a in that gure. The several drawing operations, however, do not have any thin ning action whatever in so far as the central portion of the bottom of the cup is concerned, nor do they affect its size, the bottom of the last re-draw a being of the same thickness as the original blank 12 and of the same size as the central portion of the bottom of the cup (1 and of the several intermediate re-draws, as represented in Fig. 8. The side wall of the last re-draw a is about two thousandths of an inch thinner than the blank. The final product A represented in Fig. 9, differs from the last redraw a only in that its rough edge has been cut off and that it has, or may have, been subjected to a cleaning treatment ofsome character. I

Reverting to Fig. 3, 24 indicates the redrawing plunger, which is generally similar in shape to the plunger 21 and has its base 25 fastened to the cross-head 26; and 27 indicates the die which cooperates with said. plunger. The said die fits in a seat 28 provided in the'bolster 29, and has associated with it a guide or centering ring 30 which rests partly on the lower member and partly on the bolster, this ring having an inner diameter of such a size as to enable the work to fit therein, as represented in Fig. 3, in which figure the work may be assumed to be the cup a. The die 27 is likewise annular in form, and its inner wall is provided with a circumferential shoulder or ledge 31, having a convex outer face, the lower edge of the shoulder being beveled and terminating short of the lower edge of the die, so that the shoulder thus forms a constriction or throat at the upper. end of the passage 32 in the bolster through which the re-drawing plungerv moves. The latter, as will be understood, has a diameter such that it can move through the throat.

As regards the re-drawing operation itself, it may be briefly described as follows: The cup or other work a is fitted in the guide ring 30 and thereby centered with respect of the throat or shoulder 31 and its opening, and to the passage 32,this taking place while the plunger 24 is in its raised position. The plunger then commences its descent, and gradually pushes the work ahead of it through the said throat and into the passage 32, during which time the work is elongated or stretched out and reduced in diameter, due to the pressure exerted against its side wall and the outer portion of the bottom of the cup between the opposed faces of the plunger and throat. This action continues until the plunger completes its descent and starts to ascend, whereupon the beveled edge of the shoulder will engage the upper edge of the work and strip it from the plunger, as the latter moves upward through the throat, the work falling through the passage 32. The operations just outlined are then repeated, each time with a somewhat smaller plunger and die, until the Work has been drawn out, ironed or stretched into a cup of the required size, after which the edge of the cup is trimmed off and the cup subjected to any cleaning or other further treatment or treatments which may be desired. The final product A is then fitted out with the carbon electrode, depolarizer and electrolyte in the ordinary mamier, and thereafter sealed, as indicated in Fig. 11.

In carryin out the re-drawing opera- -tions, the various sets of plungers and dies may be of such character as to permit their interchan eable attachment to, and use on,

the crossead and bolster; or, if desired,

use may be adopted,-if preferred; but since this feature in itself is not involved in the actual invention, illustration and further description thereof are considered unnecessary.

I claim as my invention: 1. A dry battery electrode in the form of cup being slightly thinner than when blanked. substantially as described.

In testimony whereof I aflix my signature.

LORENZ MAISEL,

- a seamless wrought zinc cup with its bottom 

